Air conditioner and outdoor unit thereof

ABSTRACT

An air conditioner includes a compressor, a first heat exchanger connected to the compressor through a first connection pipe, a second heat exchanger connected to the first heat exchanger through a second connection pipe and adapted to discharge super-cooled refrigerant through a third connection pipe, and a blower to blow air toward the first heat exchanger and the second heat exchanger. The first heat exchanger includes a first header in communication with the first connection pipe for introduction of the refrigerant, a plurality of tubes each having one end in communication with the first header and the other opposite end, and a second header in communication with the other end of each of the plurality of tubes. The second heat exchanger includes a heat exchange pipe that is bent plural times between the second connection pipe and the third connection pipe.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Korean Patent Application No.2009-0112434, filed on Nov. 20, 2009 in the Korean Intellectual PropertyOffice, the disclosure of which is incorporated herein by reference.

BACKGROUND

1. Field

Embodiments relate to an air conditioner having a refrigeration cyclesystem.

2. Description of the Related Art

An air conditioner is an apparatus to control, e.g., the temperature orhumidity of air through transfer of heat generated during evaporation orcondensation of a refrigerant.

Generally, a refrigeration cycle system of an air conditioner includes acompressor, a condenser, an expander, an evaporator, and pipesconnecting the above mentioned elements to one another. In circulationof a refrigerant through the pipes, the refrigerant is compressed to ahigh pressure by the compressor and then, is introduced into thecondenser. The refrigerant is condensed via heat emission while passingthrough the condenser. The condensed refrigerant is introduced into theexpander so as to be expanded to a low-temperature and low-pressurerefrigerant. As the expanded liquid-phase refrigerant is introduced intothe expander, the refrigerant is evaporated upon receiving heat from thesurrounding air while passing through the evaporator.

The performance of the air conditioner may be estimated in terms ofcooling/heating capability and energy efficiency. To enhance thecooling/heating capability and energy efficiency of the air conditioner,it may be necessary to increase heat transfer ability and efficiency ofthe condenser.

SUMMARY

Therefore, it is an aspect to provide an air conditioner having animproved refrigeration cycle system to enhance air-conditioningperformance and an outdoor unit thereof.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the invention.

In accordance with one aspect, an air conditioner includes a compressorto compress a refrigerant, a first heat exchanger arranged to undergoheat exchange with the surrounding air and connected to the compressorthrough a first connection pipe so as to condense the gas-phaserefrigerant compressed by the compressor, a second heat exchangerarranged to undergo heat exchange with the surrounding air and connectedto the first heat exchanger through a second connection pipe so as tosuper-cool the refrigerant condensed by the first heat exchanger, thesuper-cooled refrigerant being discharged through a third connectionpipe, and a blower arranged to generate air flow toward the first heatexchanger and the second heat exchanger, wherein the first heatexchanger includes a first header in communication with the firstconnection pipe for introduction of the refrigerant, a plurality oftubes each having one end in communication with the first header, and asecond header in communication with the other end of each of theplurality of tubes, and wherein the second heat exchanger includes aheat exchange pipe that is bent plural times between the secondconnection pipe and the third connection pipe.

The second heat exchanger may be arranged upstream of the first heatexchanger in a blowing direction of the blower.

The first heat exchanger may include a plurality of baffles arranged inthe first header and the second header to divide the plurality of tubesinto a plurality of groups, each of the groups may include the pluralityof tubes, and the refrigerant of the first heat exchanger may flow inthe same direction through the tubes of the same group.

Some of the plurality of groups arranged downstream in a refrigerantflow direction may include a lower number of tubes than others arrangedupstream in the refrigerant flow direction.

The second connection pipe may be connected to the first header at oneside of the first heat exchanger, and may be connected to the secondheat exchanger at one side of the second heat exchanger corresponding tothe side of the first heat exchanger.

The first heat exchanger may include a first heat exchange regiondefined between the first header and the second header, the second heatexchanger may include a first bent portion and a second bent portionarranged at opposite sides, and a second heat exchange region definedbetween the first bent portion and the second bent portion, and thefirst heat exchange region and the second heat exchange region mayoverlap each other.

The first heat exchange region and the second heat exchange region mayhave the same shape.

A distance between the first bent portion and the second bent portion ofthe second heat exchanger may be substantially equal to a distancebetween the first header and the second header of the first heatexchanger.

A height of the first heat exchange region may be substantially equal toa height of the second heat exchange region.

In accordance with another aspect, an outdoor unit of an air conditionerincludes a compressor to compress a refrigerant, a first heat exchangerconnected to the compressor so as to condense the gas-phase refrigerantcompressed by the compressor and including a first header, a secondheader and a plurality of tubes arranged between the first header andthe second header to define a first heat exchange region, a second heatexchanger connected to the first heat exchanger so as to super-cool therefrigerant condensed by the first heat exchanger and including a heatexchange pipe that is bent plural times to define a second heat exchangeregion, and a blower arranged to generate air flow passing through thefirst heat exchanger and the second heat exchanger, wherein the firstheat exchanger and the second heat exchanger are arranged parallel toeach other in a blowing direction of the blower.

The blower may include an axial flow fan, and the second heat exchanger,the first heat exchanger and the axial flow fan may be arrangedsequentially in the blowing direction.

The first heat exchange region and the second heat exchange region mayhave substantially the same shape and size.

The first heat exchanger may include a plurality of baffles arranged inthe first header and the second header to divide the plurality of tubesinto a plurality of groups, each of the groups may include the pluralityof tubes, and the refrigerant of the first heat exchanger may flow inthe same given direction when passing through the tubes of the samegroup, and may flow in different directions when passing through thetubes of the neighboring two groups.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawings of which:

FIG. 1 is a view schematically illustrating an air conditioner accordingto an embodiment;

FIG. 2 is a perspective view illustrating an outdoor unit of the airconditioner according to an embodiment;

FIG. 3 is a perspective view illustrating a fan, a first heat exchangerand a second heat exchanger included in the outdoor unit of the airconditioner according to an embodiment;

FIG. 4 is a front view of the first heat exchanger; and

FIG. 5 is a front view of the second heat exchanger.

DETAILED DESCRIPTION

Reference will now be made in detail to the embodiments, examples ofwhich are illustrated in the accompanying drawings, wherein likereference numerals refer to like elements throughout. FIG. 1 is a viewschematically illustrating an air conditioner according to anembodiment, and FIG. 2 is a perspective view illustrating an outdoorunit of the air conditioner according to an embodiment.

As shown in FIG. 1, the air conditioner 1 includes an indoor unit 2 andan outdoor unit 3. Constituent elements of a refrigeration cycle systemare mounted in the indoor unit 2 and the outdoor unit 3. Theseconstituent elements are connected to one another via a refrigerant line4.

The indoor unit 2 is arranged in an indoor space of a building to coolor heat indoor air. The outdoor unit 3 is arranged outdoors to enableheat exchange between a refrigerant circulating through the refrigerantline 4 and outdoor air. The indoor unit 2 and the outdoor unit 3 may beseparated from or integrated with each other.

In one example in which an indoor unit functions as a cooler, the indoorunit 2 includes an evaporator 10. As a fan 14 is driven by a motor 12,indoor air is fed toward the evaporator 10. A refrigerant passingthrough the evaporator 10 is evaporated by absorbing heat from theindoor air fed by the fan 14, and the high-temperature indoor air iscooled and is discharged into an indoor space.

The outdoor unit 3 includes a compressor 20, a first heat exchanger 40,a second heat exchanger 60, and a blower 80.

The compressor 20 is connected to the evaporator 10 via a refrigerantpipe 4 a and compresses the evaporated refrigerant from the evaporator10, generating a high-temperature and high-pressure refrigerant.

The first exchanger 40 is arranged to undergo heat exchange with thesurrounding air and is connected to the compressor 20 via a firstconnection pipe 4 b. The compressed gas-phase refrigerant generated inthe compressor 20 is introduced into the first heat exchanger 40 and iscondensed by emitting heat to the surrounding air while passing throughthe first heat exchanger 40.

The second heat exchanger 60 is connected to the first heat exchanger 40via a second connection pipe 4 c. The second heat exchanger 60 undergoesheat exchange with the surrounding air, to super-cool the refrigerantcondensed by the first heat exchanger 40.

When the refrigerant is condensed and cooled by the sequentiallyarranged first and second heat exchangers 40 and 60, the air conditioner1 may achieve enhanced refrigerant super-cooling performance and thus,enhanced cooling capability thereof. In addition, since the second heatexchanger 60 has an interior space to accommodate a liquid-phaserefrigerant therein, the refrigerant line 4 may be filled with a greatquantity of refrigerant. This may enhance the cooling capability of theair conditioner 1 and the super-cooling efficiency of the refrigerantwithout a significant increase in condensation pressure or evaporationpressure of the refrigerant.

The blower 80 generates air flow toward the first heat exchanger 40 andthe second heat exchanger 60 as a fan 84 is rotated by a motor 82. Thesecond heat exchanger 60 may be arranged upstream of the first heatexchanger 40 in a blowing direction F of the blower 80.

The above described configuration raises the overall efficiency of thefirst heat exchanger 40 and the second heat exchanger 60. Specifically,since the refrigerant inside the second heat exchanger 60 has a lowertemperature than that of the refrigerant inside the first heat exchanger40, it may be possible to raise the efficiency of the second heatexchanger 60 when the second heat exchanger 60 first undergoes heatexchange with the blown air. Also, even if a temperature of the blownair increases due to heat transferred from the second heat exchanger 60,the refrigerant inside the first heat exchanger 40 having a relativelyhigher temperature may efficiently undergo heat exchange with theincreased temperature of air.

The super-cooled refrigerant, having passed through the second heatexchanger 60, is discharged from the second heat exchanger 60 through athird connection pipe 4 d. The discharged super-cooled refrigerant isintroduced into the expander 100 thus being lowered in pressure andthen, is fed into the evaporator 10 through a refrigerant pipe 4 e.

Although FIG. 1 illustrates the expander 100 provided in the outdoorunit 3, the expander 100 may be provided in the indoor unit 2.

As shown in FIG. 2, the outdoor unit 3 includes a box-shaped case 120.The case 120 is formed by coupling a front plate 122, a rear plate 124,both lateral plates 126 and 128, a top plate 130 and a bottom plate 132.The rear plate 124 and one lateral plate 126 may be formed of a singleright-angled panel. The rear plate 124 has a suction grill 125 forsuction of outdoor air.

The other lateral plate 128 has an opening (not shown) for passage ofthe refrigerant pipes and electric wires for power supply. A cover 134is coupled to the opening.

The front plate 122 has a discharge hole 123 to discharge air out of thecase 120. A fan guard 136 is coupled to the discharge hole 123 toprevent external impurities from entering the outdoor unit 3.

The compressor 20, the first heat exchanger 40, the second heatexchanger 60 and the blower 80 are arranged inside the case 120.

The blower 80 may include the axial flow fan 84 and the motor 82 todrive the axial flow fan 84. The blower 80 is fixed to a supportingmember 86 and in turn, upper and lower ends of the supporting member 86are coupled respectively to the top plate 130 and the bottom plate 132so as to be coupled to the case 120.

The axial flow fan 84 includes a hub 84 a coupled to a rotating shaft ofthe motor 82, and blades 84 b extending from the hub 84 a in a radialdirection and arranged in a circumferential direction of the hub 84 a.When the axial flow fan 84 is rotated by the motor 82, an air stream inan axial direction F is generated.

A partition 138 is used to separate a space for installation of thecompressor 20 from a space for installation of the axial flow fan 84. Anelectric box 140, in which a variety of electric elements areaccommodated, is arranged in an upper region of the space forinstallation of the compressor 20.

The first heat exchanger 40 and the second heat exchanger 60 arearranged between the suction grill 125 and the axial flown fan 84 in theblowing direction F of the blower 80. Outdoor air suctioned through thesuction grill 125 absorbs heat from the first heat exchanger 40 and thesecond heat exchanger 60 thus acting to cool the refrigerant and then,is discharged out of the case 120 through the discharge hole 123.

FIG. 3 is a perspective view illustrating a fan, a first heat exchangerand a second heat exchanger included in the outdoor unit of the airconditioner according to an embodiment, FIG. 4 is a front view of thefirst heat exchanger, and FIG. 5 is a front view of the second heatexchanger.

As shown in FIGS. 3 and 4, the first heat exchanger 40 is a so-calledparallel flow heat exchanger. The first heat exchanger 40 includes afirst header 42 and a second header 44 each defining a space therein,and a plurality of tubes 46 connecting the first header 42 and thesecond header 44 to each other. The first header 42, the second header44 and the tubes 46 may be made of aluminum materials having superiorheat transfer characteristics.

The first header 42 and the second header 44 extend vertically and arehorizontally spaced apart from each other by a predetermined distance onthe drawing. The first connection pipe 4 b and the second connectionpipe 4 c are connected respectively to upper and lower positions of thefirst header 42. The positions of the first connection pipe 4 b and thesecond connection pipe 4 c may be reversed.

The high-temperature and high-pressure refrigerant compressed in thecompressor 20 is introduced into the first heat exchanger 40 through thefirst connection pipe 4 b. Also, the condensed refrigerant having passedthrough the first heat exchanger 40 is fed into the second heatexchanger 60 through the second connection pipe 4 c.

One end of each of the tubes 46 is in communication with the firstheader 42, and the other opposite end of each of the tubes 46 is incommunication with the second header 44. Air paths 48 are definedbetween the respective tubes 46 to enable air passage.

The first heat exchanger 40 has a first heat exchange region 50 in whichthe refrigerant inside the first heat exchanger 40 undergoes heatexchange with the air stream. The first heat exchange region 50 may bedefined between the first header 42 and the second header 44 inconsideration of the fact that most heat exchange occurs in the airpaths 48 and the tubes 46 located between the first header 42 and thesecond header 44.

Fins 52 to facilitate heat exchange are arranged in the air paths 48.The fins 52 may be made of aluminum materials, and may be soldered tothe neighboring tubes 46. Although FIG. 4 illustrates waveform-shapedfins 52 extending between the first header 42 and the second header 44,the shape of the fins 52 may be changed.

Baffles 54 a, 54 b and 54 c are arranged in the first header 42 and thesecond header 44. The baffles 54 a, 54 b and 54 c divide the tubes 46 ofthe first heat exchanger 40 into a plurality of groups. A first group G1is divided by the baffle 54 a arranged upstream in a refrigerant flowdirection inside the first header 42. A second group G2 is definedbetween the baffle 54 a and the baffle 54 b arranged in the secondheader 44. A third group G3 is defined between the baffle 54 b insidethe second header 44 and the baffle 54 c arranged downstream of thefirst header 42. A fourth group G4 is divided by the baffle 54 carranged downstream of the first header 42.

When the refrigerant passes through the first heat exchanger 40, therefrigerant flows in the same given direction when passing through thetubes of the same group, but flows in different directions when passingthrough the tubes of the neighboring two groups.

More specifically, the high-temperature and high-pressure refrigerant,introduced into the first header 42 through the first connection pipe 4b, undergoes heat exchange with the surrounding air while flowing to thesecond header 44 through the tubes 46 of the first group G1. Therefrigerant, having passed through the tubes 46 of the first group G1,is merged into the second header 44 and thereafter, is distributed intothe tubes 46 of the second group G2. The distributed refrigerantundergoes heat exchange with the surrounding air while flowing to thefirst header 44 through the tubes 46 of the second group G2. Thereafter,the refrigerant flows to the second header 44 through the tubes 46 ofthe third group G3 and returns to the first header 42 through the tubes46 of the fourth group G4, thereby being discharged through the secondconnection pipe 4 c.

Of the first to fourth groups G1, G2, G3 and G4, some of the groupsarranged farther downstream than the other groups in the refrigerantflow direction may include a lower number of the tubes 46 than the otherupstream groups. FIG. 4 illustrates an embodiment in which the first tofourth groups G1, G2, G3 and G4 include 6, 5, 3 and 2 tubesrespectively.

The high-temperature and high-pressure refrigerant present upstream ofthe first heat exchanger 40 shows a relatively faster flow rate, whereasthe condensed refrigerant present downstream of the first heat exchanger40 shows a relatively slower flow rate. Accordingly, when therefrigerant flows through a great number of tubes upstream of the firstheat exchanger 40, heat exchange ability and efficiency may be enhanced.

Although FIG. 4 illustrates an embodiment in which the three baffles 54a, 54 b and 54 c divide the tubes into the four groups G1, G2, G3 andG4, the number of the baffles may be changed according to the number ofgroups to be divided.

The refrigerant introduced into the second heat exchanger 60 through thesecond connection pipe 4 c is super-cooled while passing through thesecond heat exchanger 60, and is discharged out of the second heatexchanger 60 through the third connection pipe 4 d.

As shown in FIGS. 3 and 5, the second heat exchanger 60 includes aserpentine heat exchange pipe 62 that is bent plural times between thesecond connection pipe 4 c and the third connection pipe 4 d. The heatexchange pipe 62 has a first bent portion 64 and a second bent portion66 arranged at opposite sides.

The refrigerant having passed through the first bent portion 64 flows tothe second bent portion 66, and the flow direction of the refrigerant isreversed at the second bent portion 66. The refrigerant having passedthrough the second bent portion 66 flows to the first bent portion 64and the flow direction of the refrigerant is again reversed at the firstbent portion 64 so as to flow to the second bent portion 66.

The second heat exchanger 60 has a second heat exchange region 70 inwhich the refrigerant inside the second heat exchanger 60 undergoes heatexchange with the air stream. The second heat exchange region 70 may bedefined between the first bent portion 64 and the second bent portion 66in consideration of the fact that most heat exchange occurs in the heatexchange pipe 62 between the first bent portion 64 and the second bentportion 66.

Fins 68 to facilitate heat exchange are coupled to the heat exchangepipe 62. The fins 68 may be press-fitted into the heat exchange pipe 62.The fins 68 are made of thin metal plates having superior heat transfercharacteristics and may be arranged between the first bent portion 64and the second bent portion 66.

As shown in FIG. 3, the second heat exchanger 60, the first heatexchanger 40 and the axial flow fan 84 are arranged sequentially in theblowing direction F. To allow the air blown by the axial flow fan 84 topass through the second heat exchanger 60 and the first heat exchanger40 in sequence, the first heat exchange region 50 of the first heatexchanger 40 and the second heat exchange region 70 of the second heatexchanger 60 may overlap each other. This arrangement may provide theoutdoor unit 3 with compactness and the second heat exchanger 60 withenhanced efficiency, causing enhanced super-cooling performance andcooling capability of the air conditioner 1.

As shown in FIGS. 4 and 5, the first heat exchange region 50 and thesecond heat exchange region 70 may have substantially the same shape andsize. A distance D1 between the first header 42 and the second header 44of the first heat exchanger 40 may be substantially equal to a distanceD2 between the first bent portion 64 and the second bent portion 66 ofthe second heat exchanger 60. Also, a distance H1 between the uppermostand lowermost tubes of the first heat exchanger 40 (i.e. a height of thefirst heat exchange region 50) may be substantially equal to a distanceH2 between upper and lower ends of the heat exchange pipe 62 of thesecond heat exchanger 60 (i.e. a height of the second heat exchangeregion 70).

In the meantime, as shown in FIG. 2, the second connection pipe 4 c maybe connected to the first header 42 at one side of the first heatexchanger 40 and also, may be connected to the second heat exchanger 60at one side of the second heat exchanger 60 corresponding to the side ofthe first heat exchanger 40. This configuration simplifies pipingbetween the first heat exchanger 40 and the second heat exchanger 60,realizing compactness of the outdoor unit 3.

As apparent from the above description, the air conditioner according tothe embodiment having the above described configuration may exhibitenhanced capability and efficiency, resulting in excellent performancewithout using a large size outdoor unit.

Although a few embodiments have been shown and described, it would beappreciated by those skilled in the art that changes may be made inthese embodiments without departing from the principles and spirit ofthe invention, the scope of which is defined in the claims and theirequivalents.

1. An air conditioner, comprising: a compressor configured to compress arefrigerant; a first heat exchanger arranged to exchange heat with thesurrounding air and connected to the compressor through a firstconnection pipe so as to condense the gas-phase refrigerant compressedby the compressor; a second heat exchanger arranged to exchange heatwith the surrounding air and connected to the first heat exchangerthrough a second connection pipe so as to super-cool the refrigerantcondensed by the first heat exchanger, the super-cooled refrigerantbeing discharged through a third connection pipe; and a blower arrangedto generate air flow toward the first heat exchanger and the second heatexchanger, wherein the first heat exchanger includes a first header incommunication with the first connection pipe for introduction of therefrigerant, a plurality of tubes each having one end in communicationwith the first header, and a second header in communication with theother end of each of the plurality of tubes, and wherein the second heatexchanger includes a heat exchange pipe that is bent plural timesbetween the second connection pipe and the third connection pipe.
 2. Theair conditioner according to claim 1, wherein the second heat exchangeris arranged upstream of the first heat exchanger in a blowing directionof the blower.
 3. The air conditioner according to claim 1, wherein: thefirst heat exchanger includes a plurality of baffles arranged in thefirst header and the second header to divide the plurality of tubes intoa plurality of groups; each of the groups includes the plurality oftubes; and the refrigerant of the first heat exchanger flows in the samedirection through the tubes of the same group.
 4. The air conditioneraccording to claim 3, wherein some of the plurality of groups arrangeddownstream in a refrigerant flow direction include a lower number oftubes than others arranged upstream in the refrigerant flow direction.5. The air conditioner according to claim 1, wherein the secondconnection pipe is connected to the first header at one side of thefirst heat exchanger, and is connected to the second heat exchanger atone side of the second heat exchanger corresponding to the side of thefirst heat exchanger.
 6. The air conditioner according to claim 1,wherein: the first heat exchanger includes a first heat exchange regiondefined between the first header and the second header; the second heatexchanger includes a first bent portion and a second bent portionarranged at opposite sides, and a second heat exchange region definedbetween the first bent portion and the second bent portion; and thefirst heat exchange region and the second heat exchange region overlapeach other.
 7. The air conditioner according to claim 6, wherein thefirst heat exchange region and the second heat exchange region have thesame shape.
 8. The air conditioner according to claim 6, wherein adistance between the first bent portion and the second bent portion ofthe second heat exchanger is substantially equal to a distance betweenthe first header and the second header of the first heat exchanger. 9.The air conditioner according to claim 6, wherein a height of the firstheat exchange region is substantially equal to a height of the secondheat exchange region.
 10. An outdoor unit of an air conditioner, theoutdoor unit comprising: a compressor configured to compress arefrigerant; a first heat exchanger connected to the compressor so as tocondense the gas-phase refrigerant compressed by the compressor andincluding a first header, a second header and a plurality of tubesarranged between the first header and the second header to define afirst heat exchange region; a second heat exchanger connected to thefirst heat exchanger so as to super-cool the refrigerant condensed bythe first heat exchanger and including a heat exchange pipe that is bentplural times to define a second heat exchange region; and a blowerarranged to generate air flow passing through the first heat exchangerand the second heat exchanger, wherein the first heat exchanger and thesecond heat exchanger are arranged parallel to each other in a blowingdirection of the blower.
 11. The outdoor unit according to claim 10,wherein: the blower includes an axial flow fan; and the second heatexchanger, the first heat exchanger and the axial flow fan are arrangedsequentially in the blowing direction.
 12. The outdoor unit according toclaim 10, wherein the first heat exchange region and the second heatexchange region have substantially the same shape and size.
 13. Theoutdoor unit according to claim 10, wherein: the first heat exchangerincludes a plurality of baffles arranged in the first header and thesecond header to divide the plurality of tubes into a plurality ofgroups; each of the groups includes the plurality of tubes; and therefrigerant of the first heat exchanger flows in the same givendirection when passing through the tubes of the same group, and flows indifferent directions when passing through the tubes of the neighboringtwo groups.
 14. The outdoor unit according to claim 10, furthercomprising a box-shaped case, the case being formed by coupling a frontplate, a rear plate, two lateral plates, a top plate and a bottom plate.15. The outdoor unit according to claim 14, wherein the compressor, thefirst heat exchanger, the second heat exchanger and the blower arearranged inside the case.
 16. The outdoor unit according to claim 15,wherein the first heat exchanger and the second heat exchanger arearranged between the rear plate and the blower in a blowing direction ofthe blower.